With age, structural and functional changes can be observed in human cornea. Some studies have shown a loss of corneal transparency and an increase in turbidity associated with aging. These changes are caused by modifications in the composition and arrangement of extracellular matrix in the corneal stroma. In human skin, it is well documented that exposure to solar radiation, and mainly to the UVA wavelengths, leads to phenotypes of photoaging characterized by alteration in extracellular matrix of the dermis. Although the cornea is also exposed to solar radiation, the extracellular matrix modifications observed in aging corneas have been mainly attributed to chronological aging and not to solar exposure. To ascertain the real implication of UVA exposure in extracellular matrix changes observed with age in human cornea, we have developed a model of photoaging by chronically exposing corneal stroma keratocytes with a precise UVA irradiation protocol. Using this model, we have analyzed UVA-induced transcriptomic and proteomic changes in corneal stroma. Our results show that cumulative UVA exposure causes changes in extracellular matrix that are found in corneal stromas of aged individuals, suggesting that solar exposure catalyzes corneal aging. Indeed, we observe a downregulation of collagen and proteoglycan gene expression and a reduction in proteoglycan production and secretion in response to cumulative UVA exposure. This study provides the first evidence that chronic ocular exposure to sunlight affects extracellular matrix composition and thus plays a role in corneal changes observed with age.
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http://dx.doi.org/10.1111/acel.12324 | DOI Listing |
Annu Rev Biomed Eng
January 2025
1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA; email:
Biochemical signals in native tissue microenvironments instruct cell behavior during many biological processes ranging from developmental morphogenesis and tissue regeneration to tumor metastasis and disease progression. The detection and characterization of these signals using spatial and highly resolved quantitative methods have revealed their existence as matricellular proteins in the matrisome, some of which are bound to the extracellular matrix while others are freely diffusing. Including these biochemical signals in engineered biomaterials can impart enhanced functionality and native-like complexity, ultimately benefiting efforts to understand, model, and treat various diseases.
View Article and Find Full Text PDFACS Biomater Sci Eng
January 2025
Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, P. R. China.
Bacterial biofilms, complex microbial communities encased in a protective extracellular matrix, pose a significant threat to public health due to their inherent antibiotic resistance. This review explores the potential of peptides, particularly antimicrobial peptides (AMPs), as innovative tools to combat biofilm-related infections. AMPs, characterized by their potent antimicrobial activity and tissue permeability, offer a promising approach to overcome the challenges posed by biofilms.
View Article and Find Full Text PDFJ Am Soc Nephrol
January 2025
Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Background: Deficiency of adiponectin and its downstream signaling may contribute to the pathogenesis of kidney injury in type 2 diabetes. Adiponectin activates intracellular signaling via adiponectin receptors 1 and 2 (AdipoR1 and AdipoR2), but the role of AdipoR-mediated signaling in glomerular injury in type 2 diabetes remains unknown.
Methods: The expression of AdipoR1 in the kidneys of people with type 2 diabetes and the expression of podocyte proteins or injury markers in the kidneys of AdipoR1-knockout (AdipoR1-KO) mice and immortalized AdipoR1-deficient human podocytes were investigated by immunohistochemistry and immunoblotting.
FASEB J
January 2025
Stem Cell and Biotherapy Technology Research Center, School of Life Science and Technology, Xinxiang Medical University, Xinxiang, China.
Pulmonary fibrosis (PF) is a chronic and progressive interstitial lung disease characterized by abnormal activation of myofibroblasts and pathological remodeling of the extracellular matrix, with a poor prognosis and limited treatment options. Lung transplantation is currently the only approach that can extend the life expectancy of patients; however, its applicability is severely restricted due to donor shortages and patient-specific limitations. Therefore, the search for novel therapeutic strategies is imperative.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
January 2025
Vascular Biology Center and Department of Medicine, Medical College of Georgia at Augusta University, Augusta, GA USA.
The contribution of sex hormones to cardiovascular disease, including arterial stiffness, is established; however, the role of sex chromosome interaction with sex hormones, particularly in women, is lagging. Arterial structural stiffness depends on the intrinsic properties and transmural wall geometry that comprise a network of cells and extracellular matrix (ECM) proteins expressed in a sex-dependent manner. In this study, we used four-core genotype (FCG) mice to determine the relative contribution of sex hormones versus sex chromosomes or their interaction with arterial structural stiffness.
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